C/C++ : fftw Tutorial

FFTW is a C subroutine library for computing the discrete Fourier transform (DFT) in one or more dimensions, of arbitrary input size, and of both real and complex data. I use this library for compute FFT because the library is fast and simple to use. This is my fftw tutorial. So, from this fftw tutorial, you can know how to use fftw library to process your data.

I create four function in this fftw tutorial. The function is how to compute fft and ifft for your data with input/output in floating point and double data format. You can use this fftw tutorial function like at Matlab function. When using fft and ifft in Matlab, we can use this command :

The fftw accepted input data with fftwf_complex (floating point data format) and fftw_complex (double data format). This data format (fftwf_complex and fftw_complex) is an array 2D with length of colum = 2. The first column is real data and the second column is imaginer data.